MESSAGING API
RCS API for Rich Messaging at Scale
Upgrade your communication without sacrificing performance or reach. The Esendex RCS API brings the familiarity of SMS together with the engagement of rich media, giving your business the power to send branded, interactive messages that drive action.
Designed for both developers and no-code teams, it offers simple integration, reliable performance, and 24/7 expert support.
Integrate the future of business messaging
Rich experiences
Use our RCS business messaging API to send videos, carousels, maps, and suggested actions that transform customer communication beyond SMS.
Branded and trusted
Messages are sent from a verified business profile that carries your name, logo, and colours, supported by 99.9% uptime for reliable delivery.
Effortless integration
With simple documentation, multi-language code samples, and 24/7 expert support, our API makes adding RCS messaging straightforward.
> 1bn users
Over one billion people actively use RCS messaging every month, making it one of the fastest-growing global channels.
99.9% uptime
With 99.9% uptime, the Esendex API ensures your RCS messages are delivered quickly, securely, and at scale.
< 2 hours
Most businesses send their first RCS message in under two hours with our simple set up, integration and expert support.
Built by developers, for developers. Integrate our APIs for simple, real-time communication
Use our API documentation to integrate Esendex’ services into your systems within minutes. Here’s how to send an SMS:
// The POST v1/messages endpoint allows you to send a message to a single contact in one request.
// The message can also be sent via different channels; including SMS, Whatsapp and RCS.
curl -X POST 'https://api.esendex.co.uk/v2/messages' -H 'X-Api-Key: {{your-key-here}}' -H 'Content-Type: application/json' -d
{
"accountReference": "EXxxxxxxxx",
"name": "name",
"characterSet": "characterSet",
"channel": "channel",
"from": "from",
"validity": "2025-07-30T09:38:04.4517739+00:00",
"messageType": "messageType",
"body": {
"text": "text",
"templateId": "templateId"
},
"recipients": [
{
"msisdn": "msisdn",
"variables": {},
"metaData": {}
}
],
"addressBook": {
"contacts": [
{
"id": "id"
}
]
},
"metaData": {}
}No commitment, 30 day free trial
Begin your journey by opening a free Esendex account today and get 100 SMS credits.
Ready? Set? Go!
Learn how to get your service up and running with our simple quickstart guides.
Not a coder? We’ve got you covered
Our managed services team can help you set up and run your SMS API at no extra cost. From initial configuration to testing and live deployment, we’ll make sure everything is in place so you can start sending messages with confidence.
“The Esendex range of products greatly enhance the way we speak with our customers from sales follow-ups and engineer appointment confirmations, all the way through to general Q&As.”
Arron Alderson – Solutions and Process Manager, Vaillant
Let’s start sending, together.
Discover the full power of our mobile messaging platform.
Why choose Esendex?
Having us in your corner ensures that you can support your customers and your business – whatever comes your way.
20+ years of experience
Industry leading support
An expert and reliable partner
One-on-one with everyone
Flexible and scalable options
Solutions designed for you
Get the most out of RCS with our powerful API
Marketing campaigns
Deliver visually rich campaigns with carousels, images, videos, and interactive buttons.
Customer service
Support customers with two-way conversations that include maps, QR codes, and suggested actions.
Updates and reminders
Send dynamic appointment reminders, payment prompts, and real-time delivery notifications.
Rich messages
Go beyond SMS with branded media, interactive templates, and suggested replies.
Branded profiles
Reassure customers with verified sender IDs that display your company name, logo, and colours.
Powerful automation
Build intelligent workflows that trigger automated messages and replies at the right time.
FAQs
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What’s the difference between RCS and SMS?
What’s the difference between RCS and SMS?SMS is a universal, text-only channel delivered over the mobile network and supported by every handset. RCS (Rich Communication Services) uses mobile data or Wi-Fi to deliver messages, enabling richer content such as images, videos, buttons, and branded business profiles. Read our guide to learn more.
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Can all devices receive RCS messages?
RCS messaging is available on Android devices running version 5.0 or higher, and on iPhones using iOS 18.2 or later. If a device doesn’t support RCS, our API automatically falls back to SMS.
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Is the RCS API secure and GDPR compliant?
Yes. The Esendex API is fully compliant with GDPR and ISO 27001.
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How quickly can I start sending messages with the RCS API?
Most teams send their first RCS message in under two hours thanks to simple integration and expert support.
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Do I need coding skills to use the RCS API?
No. Our managed services team make it easy to get started without technical resources.
